Connector-Based Optical Identification Apparatus and Method

ABSTRACT

An apparatus includes a device interface system having a first connector and second connector, each with a respective optical signal path arrangement operatively aligned when the two connectors are in a connected position. The operative alignment allows a base optical signal to be transmitted from the first connector to the second connector. An optical signal modification arrangement is included in the second connector and is operable to provide a predefined modification to the base optical signal to result in an optical ID signal that is transmitted back to the first connector. An identification processing unit associated with the first connector receives an ID input signal corresponding to the optical ID signal and produces an identification output responsive to the ID input signal.

TECHNICAL FIELD OF THE INVENTION

The invention relates to apparatus and methods which can be employed toidentify a device when it is connected in a system. For example, thepresent identification apparatus may be employed to identify a medicalinstrument such as an endoscope as the instrument is connected to acontrol unit for the instrument.

BACKGROUND OF THE INVENTION

Many types of devices such as instruments for medical and otherapplications operate through a connection to a separate control unitwhich provides power and control signals, and may also receive data orsome other output from the connected device. In some cases there is somedegree of interchangeability in the types of devices that may bephysically connected to a given control unit. In these cases it isnecessary to ensure that the intended device is connected to the controlunit for a given application of the system. However, it may be difficultfor device operators to distinguish between different devices which mayhave similar appearance and differ only in technical capability. Also,particularly medical instruments may be limited to a maximum number ofuses or a maximum number of uses before some manner of service isrequired to ensure proper operation of the instrument.

Systems have been developed to assist in identifying a device such as amedical instrument to be connected in a system for operation. Forexample, U.S. Patent Application Publication No. 2004/0122419 A1discloses a system particularly for use in recognizing disposable orreusable optical components that may be connected to a radiation sourceunit, and for maintaining usage information on such optical components.The system disclosed in this publication employs a radio frequencyidentification (RFID) transponder located with the connectable device tocommunicate with the unit to which it is connected. However, radiofrequency devices such as these are susceptible to electromagneticinterference which can limit the application and effectiveness of thesystem.

U.S. Pat. No. 4,878,896 to Garrison et al. discloses an identificationarrangement for use with a medical infusion system. The system disclosedin this patent employs a series of light sources and light sensorslocated on an infusion pump. The light sources and light sensorscooperate with elements on a pump-mounted cassette to provideidentification information regarding the cassette. The identificationarrangement disclosed in Garrison et al. is cumbersome and not suitedfor use in many applications in which connected device identification isdesired.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an identificationapparatus that may be associated with an arrangement of connectorsproviding an interface between a device and a control unit for thedevice. The invention encompasses an apparatus including bothconnecter-mounted components and a processing unit which need not bemounted on a connector. The invention also encompasses an arrangement ofconnector-mounted components to facilitate device identification, aninstrument having a connector incorporating identification components,and methods for providing an identification output after a connectionbetween a device and a control unit for the device.

An apparatus according to one aspect of the present invention includes adevice interface system having a first connector and second connector.The first connector includes an optical signal transmission patharrangement and an optical signal receiving path, while the secondconnector includes an optical signal return path arrangement extendingfrom an input end to an output path. The second connector is configuredto connect to the first connector in an operating position in which theinput end of the optical signal return path arrangement is operativelyaligned with the optical signal transmission path arrangement and theoutput path is operatively aligned with the optical signal receivingpath. Operative alignment in this sense and as used elsewhere in thisdisclosure and the claims means that the optical signal paths arealigned so that optical energy may propagate from one optical path tothe other with only acceptable losses under the circumstances. Theapparatus according to this aspect of the present invention alsoincludes an optical signal modification arrangement operable to providea predefined modification to a base optical signal applied at the inputend of the optical signal return path arrangement. This predefinedmodification results in an optical ID signal applied at the output pathof the optical signal return path arrangement. An optical transmitterarrangement and an optical receiver are also included in the apparatus.The optical transmitter arrangement is operable to apply the baseoptical signal including two or more optical signal components to theoptical signal transmission path arrangement, while the optical receiveris operable to receive the optical ID signal from the optical signalreceiving path and produce an ID input signal responsive to the receivedoptical ID signal. An identification processing unit which receives theID input signal produces an identification output responsive to the IDinput signal.

According to this first aspect of the present invention, the predefinedmodification which may be applied to the base optical signal when thefirst and second connectors are in the operating position encodesinformation about the second connector or a device associated with thesecond connector into the base optical signal and thereby produces theoptical ID signal. This information may be correlated to one or morecharacteristics of the second connector or device associated with thesecond connector. For example, the second connector may comprise aconnector of a medical instrument which is adapted to connect to acomplementary connector of a control unit for the medical instrument.The optical ID signal, that is, the base optical signal modifiedaccording to the predefined modification, may correlate to a type ofmedical instrument, operating parameters or limitations of the medicalinstrument, or perhaps a specific identifier for the medical instrumentsuch as a serial number for the instrument. Regardless of thecharacteristics of the second connector or the connected device whichmay be discerned by an analysis of the optical ID signal, theidentification output may prompt any number of responses appropriate tothe situation. In the medical instrument example, the identificationoutput may prompt the medical instrument control unit to power up theconnected medical instrument and/or send data such as operatingparameters to the medical instrument. Alternatively, in the event thedetected characteristic of the connected medical instrument indicatesthat the medical instrument is inappropriate in some fashion, theidentification output may prevent the medical instrument control unitfrom powering up the instrument or otherwise cause the instrument to beinoperable.

An identification apparatus according to this first aspect of theinvention allows characteristics of a device such as a medicalinstrument to be identified upon connection to a control unit prior toany power being applied to the instrument and without any electroniccommunications to or from the instrument. With the absence of electroniccommunications to or from the instrument, the identification process maybe entirely immune to electromagnetic interference which could affectthe accuracy of the identification. Embodiments according to this firstaspect of the invention may also ensure that the required electricalisolation barrier is maintained across the connectors. Also, theidentification apparatus is capable of providing large amounts of datafor identification while maintaining a very compact form factor.

In an apparatus according to the first aspect of the invention, theidentification processing unit may comprise data storage and a suitableprocessor. The data storage stores a number of ID signatures with eachrespective ID signature being related in the data storage arrangement torespective connectable device information, such as a device type, serialnumber, or other device-specific information. The processor is operableto, in response to the received ID input signal, locate a stored IDsignature corresponding to the ID input signal and then retrieve therespective connectable device information related to the located IDsignature. The processor then generates the identification output basedon the retrieved device information.

In this disclosure and the following claims the term “arrangement” whenused in connection with an optical signal path or other physicalstructure means that the referenced physical structure may include oneor more components. For example, an optical signal path arrangement mayinclude one or more optical paths such as optical waveguides forcarrying the different optical components of an optical signal. Eachrespective optical component may be carried by a respective opticalwaveguide in the optical signal path arrangement. Thus an optical signaltransmission path arrangement according to the first and other aspectsof the present invention may include a number of different transmissionoptical waveguides corresponding to the number of optical componentsincluded in the base optical signal. Similarly, the optical signalreturn path arrangement may include a number of different return opticalwaveguides corresponding to the number of optical components included inthe base optical signal. Implementations having multiple differentreturn optical waveguides may include an optical coupler to opticallycouple each return optical waveguide to the output optical waveguide ofthe second connector.

An apparatus according to another aspect of the present inventionincludes an instrument such as a medical or industrial instrument and aconnector to the instrument. The instrument connector may also bereferred to as a device-side connector and is configured to connect inan operating position with a control unit connector, that is, a controlunit-side connector, associated with a control unit for the instrument.An apparatus according to this second aspect of the present inventionfurther includes an optical signal return path arrangement mounted inthe instrument connector and also includes an optical signalmodification arrangement associated with the optical signal return patharrangement. The optical signal return path arrangement here correspondsto the optical signal return path arrangement discussed above inconnection with the previously described aspect of the invention.Similarly, the optical signal modification arrangement corresponds tothat element of the previously described aspect of the invention.

In one implementation according to either of the foregoing aspects ofthe invention, the optical signal modification arrangement comprises atleast one optical signal attenuator. Where the optical signal returnpath arrangement includes multiple return optical waveguides, eachrespective optical attenuator may be operatively connected in arespective one of the return optical waveguides. Otherwise, each opticalattenuator may comprise a device that selectively attenuates a givenbase optical signal component propagating along a single waveguide.These alternatives will be described in further detail below inconnection with a representative embodiment and variations on thatembodiment.

In another implementation according to either of the foregoing aspectsof the invention including two or more return optical waveguides, thereturn optical waveguides may each include a respective end portionextending substantially parallel to an output end of the output opticalwaveguide. Similarly, in implementations according to the first aspectof the present invention having two or more transmission opticalwaveguides, each such waveguide may include a respective transmissionend portion extending substantially parallel to a receiving end portionof the receiving optical waveguide. This arrangement of opticalwaveguides facilitates a compact assembly of the connector-mountedcomponents of the identification apparatus with the component alignedacross an interface plane between the connectors in the operatingposition.

In another implementation according to either of the foregoing aspectsof the invention, the optical signal return path arrangement is mountedin a return unit in the second connector. The return unit may include areturn alignment block which is mounted in the second connector.Similarly, in an implementation according to the first aspect of theinvention, the optical signal transmission path arrangement and theoptical signal receiving path are mounted within a send/receive unit ofthe first connector which may include a send/receive alignment block.

Another aspect of the invention includes a method for identifying aconnector or a device associated with a connector. The method accordingto this aspect of the invention includes transmitting the base opticalsignal from a first connector to a second connector, and directing thebase optical signal along the optical return path arrangement associatedwith the second connector. The method further includes applying apredefined modification pattern to the two or more base optical signalcomponents of the base optical signal as the signal is directed throughthe optical signal return path arrangement. As in the first aspect ofthe invention described above, this predefined modification patternresults in an optical ID signal applied at the output waveguide of theoptical signal return path arrangement. The method also includesdirecting the optical ID signal from the output waveguide to a receivingoptical waveguide of the first connector, receiving the optical IDsignal at the first connector and producing an identification output inresponse to the received optical ID signal.

As in the previously described aspects of the present invention, thepredefined modification pattern may be a pattern of signal attenuationamong the two or more base optical signal components. Also, each baseoptical signal component may be transmitted or directed over a differentoptical waveguide in the respective optical signal path arrangement.

According to any of the above-described aspects of the invention, thetwo or more base optical signal components may be offset temporally.Furthermore, each of the two or more base optical signal components maybe transmitted at a different respective modulation frequency or othercharacteristic which facilitates encoding information into the baseoptical signal itself.

These and other advantages and features of the invention will beapparent from the following description of representative embodiments,considered along with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of an example system in which anidentification apparatus according to one aspect of the invention isimplemented.

FIG. 2 is a schematic representation of the interface shown in FIG. 1,together with additional components of an example identificationapparatus.

FIG. 3 is a signal diagram showing a representative set of base opticalsignal components according to one implementation of the presentinvention, and also showing three examples of optical ID signals whichmay be produced from the base optical signal components.

FIG. 4 is a flow diagram showing a process performed on a controlunit-side connector of the system shown in FIG. 1.

FIG. 5 is a flow diagram showing a process performed at a device-sideconnector of the system shown in FIG. 1.

FIG. 6 is a perspective view of a device-side connector according to oneaspect of the present invention.

FIG. 7 is a perspective view of a control unit-side connector adapted tocooperate with the device-side connector of FIG. 6 to provide anoperative connection between a control unit and a device associated withthe device-side connector.

FIG. 8 is a perspective view of a medical device operatively connectedto the device-side connector shown in FIG. 6.

DESCRIPTION OF REPRESENTATIVE EMBODIMENTS

The various aspects of the present invention are described below in thecontext of an observation instrument system, particularly an endoscopicsystem. However, the present invention is not limited to thisrepresentative application. Thus, observation instruments (e.g., a videocameras, endoscopes, exoscopes, borescopes) employing high-resolutionimaging (e.g., a 4K resolution design) represent merely an illustrative,but non-limiting example application of various aspects of the presentinvention. More generally, an apparatus and method within the scope ofthe following claims may have application in substantially any interfacesystem to a given device in which it is desirable to automaticallyidentify some characteristic of the given device at the time it isconnected via the interface system.

FIG. 1 shows an endoscopic system 100 employing an interface device 101in which portions of an identification apparatus according to someaspects of the present invention are implemented. System 100 includes acamera control unit (“CCU”) 104, a camera head 105, and an endoscope106. CCU 104 is connected to send a signal to a monitor control unit 108which is in turn connected to monitors 109 for displaying images fromcamera head 105 or endoscope 106.

Interface device 101 is interposed between CCU 104 and camera head 105and functions as a detachable link for data communication and powertransfer between the CCU and camera head. Both the data communicationand power transfer functions are preferably provided across interfacedevice 101. This example interface device 101 also maintains anelectrical isolation barrier to camera head 105 and endoscope 106 asdescribed in U.S. patent application Ser. No. 15/161,007 entitled“Apparatus and Method of Providing an Interface to an ElectricallyPowered Instrument,” the entire content of which is incorporated hereinby this reference. Data is communicated in the form of optical datasignals S in FIG. 1 bidirectionally, both from camera head 105 and/orendoscope 106 to CCU 104 and also preferably in the opposite directionfrom the CCU to the camera head and/or endoscope. Electrical power (P inFIG. 1) is transferred unidirectional, in the direction from CCU 104 tocamera head 105 and/or endoscope 106.

Interface device 101 includes a first connector 111 and a secondconnector 112 which may be connected in an operating position tofacilitate the desired data communication and power transfer between CCU104 and the combination of camera head 105 and endoscope 106. In thecontext of system 100, first connector 111 may be referred to as acontrol unit-side connector in this embodiment since it is associatedwith a control unit, namely CCU 104, for the device to be connected (thecombination of camera head 105 and endoscope 106). Similarly, secondconnector 112 may be referred to as a device-side connector in thisembodiment since it is associated with the devices or instruments to beconnected to a control or other unit.

The operating position between first connector 111 and second connector112 is schematically indicated in FIG. 1 and will be described infurther detail below with reference particularly to FIG. 2. The twoconnectors 111 and 112 may be readily separated to detach camera head105 and endoscope 106 from CCU 104 and then reconnected in the operatingposition as desired. For example, connector 112 may be detached fromconnector 111 in preparation for sterilizing camera head 105 and/orendoscope 106. Once the sterilization or other process or activityrequiring detachment is complete, connectors 111 and 112 may be readilyconnected back together again in the operating position to againfacilitate data communication and power transfer between CCU 104 andcamera head 105/endoscope 106.

The position of interface device 101 shown in FIG. 1 between CCU 104 andcamera head 105 is intended to indicate that the interface device may beinterposed at any position between those two system components. Oneembodiment that will be described further below in connection with FIGS.2 and 7 incorporates first connector 111 in a housing for CCU 104. Inthis embodiment, first connector 111 may be formed as a receptacle in ahousing for CCU 104 and adapted to receive second connector 112 in theoperating position. Second connector 112 in this embodiment is connectedto a suitable cable having optical conduits such as optical fibers forcarrying the optical signals and suitable conductors for conductingelectrical power to camera head 105. However it should be borne in mindthat the invention is not limited to this arrangement in which one ofthe connectors is incorporated in a control unit such as the CCU 104 orone of the other components in the system.

FIG. 1 shows that interface unit 101 also includes a send/receive unit115 and a return unit 116 mounted on the first and second connectors,111 and 112, respectively. These units 115 and 116 each include opticalsignal path arrangements which are part of an identification apparatusaccording to various implementations of the present invention. Theseoptical signal path arrangements together with other elements associatedwith the various optical signal paths included in the arrangements willbe discussed below in connection with FIG. 2. As will be described belowparticularly in connection with the example signals shown in FIG. 3, theoptical signal paths and cooperating elements in send/receive unit 115and return unit 116 cooperate to provide an optical ID encoded withinformation correlated to one or more characteristics of camera head 105and/or endoscope 106 (in this representative example).

Before moving on to describe further details of an exampleidentification apparatus, it should be noted that both CCU 104 andcamera head 105 in this particular implementation include components forsupporting interface 101 and the associated identification apparatus. Inparticular, CCU 104 includes a transceiver unit 117 which receivesoptical signals from the direction of camera head 105 and transmitsoptical signals to the camera head and/or endoscope 106. Similarlycamera head 105 includes a transceiver unit 118 for transmitting opticalsignals to CCU 104 and for receiving incoming optical signals from theCCU. As will be described in detail with respect to FIG. 2 below,transceiver unit 117 also includes components to transmit opticalsignals to and receive optical signals from send/receive unit 115 forfacilitating the identification functionality according to the presentinvention.

FIG. 2 schematically shows further details of first connector 111 andsecond connector 112. Connector 111 has mounted therein an opticalsignal transmission path arrangement shown generally at 201. In thisillustrated implementation, optical signal transmission path arrangement201 includes four separate paths defined by separate optical waveguidessuch as suitable optical fibers 202 a, 202 b, 202 c, and 202 d.Connector 111 also includes an optical signal receiving path defined bysuitable optical waveguide such as optical fiber 204. These opticalsignal paths defined in this example by optical fibers 202 a-d and 204,together with associated elements described further below whichfacilitate sending and receiving optical signals to and from connector112, represent one embodiment of the send/receive unit 115 shown inFIG. 1. Other embodiments having more or less optical fibers are alsocontemplated. Connector 112 is shown as having an optical signal returnpath arrangement shown generally at 206. This optical signal return patharrangement 206 extends from an input end, which includes four separatepaths in this implementation, to a single output path. The four separatepaths at the input end of optical signal return path arrangement 206 mayeach comprise a suitable optical waveguide such as an optical fiber 207a, 207 b, 207 c, and 207 d. Similarly the single output path maycomprise a suitable waveguide such as optical fiber 209. In view of themultiple separate optical paths at the input end of optical signalreturn path arrangement 206 and the single output path comprising fiber209, this particular implementation also includes an optical coupler 208for coupling fibers 207 a-d to optical fiber 209. Optical signalattenuators 214 are also shown associated with the optical signal returnpath. These optical signal attenuators 214 make up an optical signalmodification arrangement of the identification apparatus and will bedescribed further below in connection with FIGS. 3 and 4. Thecombination of optical fibers 207 a-d, optical fiber 209, opticalcoupler 208, and attenuators 214, together with associated elementsdescribed below represent the return unit 116 shown in FIG. 1.

In the implementation represented schematically in FIG. 2, each fiber202 a-d terminates in a respective ferrule labeled 216 a, 216 b, 216 c,and 216 d in FIG. 2. Each fiber 207 a-d also terminates at its input endat a respective ferrule labeled 217 a, 217 b, 217 c, and 217 d in FIG.2. Similarly, FIG. 2 shows that fiber 204 of the optical signal returnpath terminates at ferrule 220, and fiber 209, which defines the opticalsignal output path associated with second connector 112, terminates atferrule 221. The embodiment illustrated in FIG. 2 employs an expandedbeam arrangement for transferring optical signals from first connector111 to second connector 112 and from the second connector 112 to thefirst connector 111. This expanded beam arrangement includes arespective spherical lens 223 a, 223 b, 223 c, and 223 d alignedrespectively with each ferrule 216 a-d in connector 111 and a respectivespherical lens 224 a, 224 b, 224 c, and 224 d aligned respectively witheach ferrule 217 a-d in connector 112. A spherical lens 225 is alsoaligned with ferrule 220 in connector 111 and a spherical lens 226aligns with ferrule 221 in connector 112. The spherical lenses of firstconnector 111 in this embodiment, lenses 223 a-d and 225, are eachlocated in a respective lens receiving opening 227 while the sphericallenses 224 a-d and 226 of second connector 112 are located in arespective lens receiving opening 228. It should be appreciated thatalthough an expanded beam arrangement is used in transferring theoptical signals employed in the apparatus illustrated in FIG. 2, theinvention is not limited to use with such arrangements. Rather, theoptical signals may be passed between the connectors 111 and 112 in anysuitable fashion. Also, where expanded beam arrangements are used, anysuitable lens may be used, for example, spliced gradient index lenses,spliced glass rods, or other collimating lenses, to expand and contractthe beams, and the invention is certainly not limited to the sphericallenses shown for example in FIG. 2.

Regardless of any arrangement of lenses to facilitate the desiredcoupling of light signals between connectors 111 and 112, it isdesirable to provide a layer of protective material in each connector toprotect the respective fibers. Thus the embodiment shown in FIG. 2includes a protective cover 229 for first connector 111 and a protectivecover 230 for second connector 112. These protective covers may comprisesapphire for example, or any other type of material which does notinterfere with the transmission of light signals between connectors 111and 112, and may be separated by an air gap 231 when the connectors 111and 112 are connected in the operating position.

With second connector 112 connected in the operating position with firstconnector 111 shown in FIG. 2, the optical signal transmission patharrangement 201 of first connector 111 is operatively aligned with theinput end of the optical signal return path arrangement 206 of secondconnector 112. The operative alignment in this case means that ferrules216 a-d on first connector 111 are each aligned with a correspondingferrule 217 a-d on second connector 112 so that optical signals exitingfibers 202 a-d are coupled into the corresponding fibers 207 a-d acrossa respective set of lenses 223 a-d and 224 a-d, protective covers 229and 230, and air gap 231. Similarly, ferrule 221 for the fiber 209defining the output path associated with connector 112 is operativelyaligned with ferrule 220 for the fiber 204 defining the optical signalreceiving path of connector 111. With this alignment, optical signalsfrom fiber 209 are coupled into fiber 204 across lenses 226 and 225,protective covers 229 and 230, and air gap 231. To help facilitate theoperative alignment between the optical paths, the ferrules andspherical lenses are shown mounted in a respective alignment block. Inparticular ferrules 216 a-d and 220 along with lenses 223 a-d and 225are mounted in an alignment block 233 of first connector 111 whileferrules 217 a-d and 221 along with lenses 224 a-d and 226 are mountedin an alignment block 234 of second connector 112.

FIG. 2 also shows transceiver 117 (also referenced above in connectionwith FIG. 1) and an identification (ID) processing unit 237. Transceiver117 comprises a suitable device for transmitting the base optical signaland for receiving the optical ID signal both under control of a suitablecontrol device such as ID processing unit 237. Because any suitableoptical transceiver may be employed in embodiments of the presentinvention and because such devices are well known in the art of opticalcommunications, transceiver 117 is shown only schematically in thefigures and details of the various components which may be included insuch a device are omitted to avoid obscuring the present invention inunnecessary detail. Those familiar with optical signal communicationswill appreciate that a suitable transceiver may include a respectivetransmitter such as an electro-optical converter for each fiber 202 a-dof optical signal transmission path arrangement 201, and a suitablereceiver such as an opto-electrical converter for the fiber 204 definingthe optical signal receiving path of connector 111. It will also beappreciated that suitable circuitry is included in transceiver 117 forreceiving control signals from the associated controller and producing asignal to drive the transmitter(s) and for conditioning the receiveroutput for use by ID processing unit 237. It should be noted here thatthe present invention is not limited to any particular wavelength ofoptical signal for the base optical signal. Rather a base optical signalaccording to the invention may comprise any light signal that issuitable for propagating through the various optical paths included inthe apparatus and amenable for the desired encoding in the secondconnector and for reception at a suitable receiver.

ID processing unit 237 includes a suitable processor 242 and datastorage 243 accessible to the processor. Because connector 111 isintegrated with CCU 104 in this particular embodiment of theidentification apparatus, transceiver 117, processor 242, and storage243 may not be components dedicated to the functionality of theidentification apparatus. Thus transceiver 117 may include additionaltransmitters and receivers together with associated circuitry forfacilitating the desired communication link between CCU 104 and camerahead 104/endoscope 106. These transmitters and receivers are omittedfrom FIG. 2 similarly to the corresponding elements associated with theidentification apparatus. Also processor 242 in this embodiment mayprovide functionality for the operation of CCU 104 in addition to thefunctionality of the identification processing unit 237. Similarly datastorage 243 may be general data storage (including one or more datastorage devices) associated with CCU 104 and may not be dedicated forstoring identification information as described further below. Ofcourse, other embodiments of an identification apparatus within thescope of the present invention may include optical transmitters andreceivers that are included in a transceiver dedicated exclusively foroptical signal transmission and reception for purposes of identificationfunctionalities. The processing unit and associated data storage forproviding the desired identification functionality may likewise bedevices dedicated to the identification apparatus. In either case, theprocessor may comprise any suitable digital processor such as a generalpurpose processor, a field programmable gate array, or an applicationspecific integrated circuit, or combinations of these types of devices.

Because connectors 111 and 112 are connectors for the interface device101 shown in FIG. 1, the connectors include components for providing thedesired communication link between the CCU 104 and camera head105/endoscope 106 shown in FIG. 1. These components are shown in FIG. 2as an interface 245 in first connector 111 and interface 246 in secondconnector 112. These interfaces are shown schematically in FIG. 2because the specific way in which they provide the desired operativelink between the connected device, in this case camera head 105 andendoscope 106, and their control unit, in this case CCU 104, are notrelevant to the identification apparatus which is the subject of thisdisclosure. However, it will be appreciated that interfaces 245 and 246are located within the respective connector 111 and 112 preferably suchthat they form the desired operable communication link between CCU 104and camera head 105 when the various optical paths of the identificationapparatus are brought into the operative alignment shown in FIG. 2. Thissimultaneous operative alignment for elements of the identificationapparatus and interfaces 245 and 246 may be facilitated by placing theelements in common alignment blocks for the two connectors 111 and 112.Although interfaces 245 and 246 may take any form suitable for providingthe operative link between the devices in question, example interfacesthat may be used in particular between an observation unit such ascamera head 105/endoscope 106 and a control unit such as CCU 104 aredescribed in detail in the aforementioned U.S. patent application Ser.No. 15/161,007.

The signal diagram of FIG. 3 shows an example of a base optical signalthat may be generated according to the present invention. The baseoptical signal in this example is made up of four different base opticalsignal components, each expressed in optical power level over time.These include a first base optical signal component shown as signal TX1,a second base optical signal component shown as signal TX2, a third baseoptical signal component shown as signal TX3, and a fourth base opticalsignal component shown as signal TX4. These base signal componentscorrespond to the signals transmitted along optical fibers 202 a, 202 b,202 c, and 202 d, respectively, in FIG. 2 and are directed across theillustrated expanded beam arrangement to optical fibers 207 a, 207 b,207 c, and 207 d, respectively, of second connector 112. In thisexample, the different base optical signal components each include anoptical signal at a different respective modulation frequency and thedifferent signals are offset temporally. Also, FIG. 3 shows each baseoptical signal component appearing twice over the course of timerepresented by the horizontal axis of FIG. 3. As will be discussedfurther below in connection with variations on this example signalarrangement, the optical signals may or may not be all at the sameoptical wavelength.

FIG. 3 also shows an optical ID signal RX DV1 that is produced by thepattern of modification applied in the optical signal return patharrangement associated with second connector 112 shown in FIG. 2. Thissignal RX DV1 comprises a signal made up of the various base signalcomponents as modified by signal attenuators 214 and combined viaoptical coupler 208. As such, signal RX DV1 is a signal present at theoutput path of second connector 112 defined by fiber 209 and the opticalreceiving path defined by fiber 204 of first connector 111 in FIG. 2responsive to the base optical signal comprising the four componentsTX1, TX2, TX3, and TX4. Thus the base signal components TX1 and TX3contributing to signal RX DV1 each remain essentially un-attenuated asthey travel along their respective fiber 207 a and 207 c in FIG. 2(aside from losses inherent in transmission through the various opticalpath components). However, the signal attenuator 214 associated withfiber 207 b in FIG. 2 attenuates the signal strength (that is, decreasesoptical signal power) by a predefined amount as indicated at 302 in FIG.3. The attenuator 214 associated with fiber 207 d similarly attenuatessignal TX4 resulting in the attenuated signal indicated at 303 in FIG.3.

FIG. 3 shows two additional signals as examples of optical ID signalsthat would be produced by a different arrangement of signal attenuatorssuch as attenuators 214 shown in FIG. 2. The signal pattern shown at RXDV2 in FIG. 3 comprises a signal pattern that would result from placinga signal attenuator 214 in each of fibers 207 b, 207 c, and 207 d of theexample device in FIG. 2, while leaving the signal in fiber 207 dessentially un-attenuated. The example signal pattern shown at RX DV3 inFIG. 3 comprises a pattern that would result where no attenuator 214 ispresent in any of the four fibers 207 a-d of second connector 112.

The three different signals RX DV1, RX DV2, and RX DV3 show how applyinga given pattern of attenuation to the optical signals making up thedifferent components TX1, TX2, TX3, and TX4 of the base optical signaloperates to encode information into the base optical signal to createoptical ID signals. For example, the un-attenuated signal component maybe defined as one binary logical state whereas the attenuated signal maybe defined as the opposite logical state. Continuing with this examplethe un-attenuated signal may be defined as a logical “1” while theattenuated signal may be defined as a logical “0.” Applying theseexample definitions, the signal RX DV1 represents an optical ID signalcarrying the binary number “1010,” signal RX DV2 represents an opticalID signal encoded as the binary number “1000.” And signal RX DV3represents an optical ID signal encoded as the binary number “1111.” Theoptical ID signal and corresponding binary representation produced by agiven signal modification arrangement of a given second connector may becorrelated to some characteristic of that connector and particularly adevice associated with the second connector. Thus the signal resultingfrom the signal modification pattern applied in a given second connectormay be decoded by an identification processing unit (237 in the exampleof FIG. 2) to obtain the characteristic associated with the encodedsignal. An example of the operations performed by the exampleidentification processing unit 237 in FIG. 2 will be described furtherbelow in connection with the flow diagram of FIG. 4.

The present invention encompasses many variations in the baseidentification signal and the signal modification shown for example inFIG. 3. For example, although FIG. 3 includes four base signalcomponents which may be encoded to represent a four-place binary number,the invention is not limited to any particular number of base signalcomponents provided there remain a sufficient number of components toproduce an identifier which may be correlated to the desired devicecharacteristic. Also, the present invention is not limited to anyparticular encoding arrangement that may be implemented by the signalmodification arrangement associated with the second connector. Forexample, although the encoding shown for example in FIG. 3 indicatesthat each base signal component may be encoded in a binary fashion, itis possible to encode each component into three or more states in orderto increase the amount of data carried by the resulting optical IDsignal. In an example of tri-state encoding, different attenuators 214in FIG. 2 might be selected to reduce the signal power by about half asshown in the attenuation indicated in FIG. 3 to provide one state inaddition to an un-attenuated state, and an attenuator blocking theoptical signal entirely might be selected to provide a third signalstate comprising essentially zero signal power. Of course, the IDprocessing unit (such as ID processing unit 237 shown in the example ofFIG. 2) would then require the capability of distinguishing the threedifferent signal states and convert that information from the ID signalinto a usable form such as a binary form.

It should also be appreciated that many different types of base opticalsignal may be employed to provide a base signal in which information maybe encoded via a suitable signal modification arrangement in a connectorsuch as second connector 112. For example, an alternative base opticalsignal that may be used in an embodiment of the present invention maycomprise a signal including different base signal components comprisingdifferent optical wavelengths. In this alternative, the signalattenuators (corresponding to example attenuators 214) may comprisewavelength-specific devices operable to attenuate only a specifiedwavelength or wavelength range included in the base optical signal. Inthat case, the resulting optical ID signal would include a signal madeof up of the various base signal components attenuated or un-attenuatedaccording to the desired encoding pattern provided by the selectedwavelength-specific attenuators comprising the signal modificationarrangement. Of course, in this wavelength-specific attenuationarrangement, the apparatus would include a suitable transmitterarrangement to generate the different wavelengths and the signalreceiving components would be required to distinguish the differentsignal wavelengths and extract the encoded information on the receivingside. One example implementation employing base optical signalcomponents at different light wavelengths may include a broadbandtransmitter for producing the base optical signal, and an arrayedwaveguide in the optical receiving path of the first connector(corresponding to connector 111 in the above-described example) toseparate the different wavelengths for reception at a respectivereceiver. One advantage of a wavelength-selective modification performedat the second connector (corresponding to connector 112 in theabove-described example) is that the optical signal transmission patharrangement and the optical signal return path arrangement may comprisea single waveguide carrying a broadband optical signal or a multiplexedwavelength signal. Signal attenuators in these wavelength-specificmodification embodiments may include suitable filters connected in theoptical signal return path waveguide to selectively attenuate certainwavelengths as desired to encode the desired information into theoptical ID signal.

Although the signal modification performed in the second connector 112is used to encode information about a characteristic of the connector ora device with which connector is associated, additional information maybe encoded into the base optical signal itself. For example, thedifferent modulation frequencies of the signals TX1, TX2, TX3, and TX4shown in FIG. 3 may be correlated to identify some characteristic of theconnector (first connector 111 in the example of FIG.2) or identify somecharacteristic of the control unit (such as CCU 104 in the example ofFIG. 1) or other device with which the connector is associated. Ofcourse the variation of optical signal modulation frequency shown inFIG. 3 simply represents an example for encoding information about thetransmitting unit into the base optical signal, and the invention is notlimited to this modulation frequency technique. For example, differentcombinations of optical wavelengths for the base optical signalcomponents may be correlated to information regarding the transmittingunit.

The flow diagrams of FIGS. 4 and 5 may now be referenced to describe theoperation of the example identification apparatus interface 101 shown inFIG. 2, and methods according to aspects of the present invention. FIG.4 shows process steps performed on the control unit-side, for examplecamera control unit 104, of the apparatus 101, while FIG. 5 showsprocess steps performed on the device-side, for example camera head 105or endoscope 106, of the apparatus 101. In the following description ofFIGS. 4 and 5 it will be appreciated that the references to theapparatus components are references to the components illustrated inFIGS. 1 and 2.

Referring now to FIG. 4, a method of identifying a connected deviceincludes first generating a base drive signal as indicated at processblock 401 in FIG. 4. This base drive signal may be generated bycircuitry associated with transceiver 117 under control of processor 242executing suitable program code, and comprises an electrical signalwhich may be applied to drive transmitters in the transceiver to producethe desired optical signals. The conversion of the electrical drivesignal to the base optical signal is shown at process block 402. Thebase optical signal is then directed from the first connector to thesecond connector as shown at process block 403. This transfer of thebase optical signal from the first to second connector is performed bythe optical signal transmission path arrangement shown generally at 201in FIG. 2, including any associated lenses such as spherical lenses 223a-d.

If no optical signal is received back at first connector 111 in responseto the transmission of the base optical signal, it can be assumed thatsecond connector 112 is not present to direct the encoded, optical IDsignal to the optical signal receiving path defined in FIG. 2 by fiber204. In this case the negative outcome at decision box 405 causes theexample process to loop back to process block 401 where the base drivesignal may be generated again periodically until an optical signal isreceived. The presence of a signal received from the optical receivingpath defined by fiber 204 indicates that second connector 112 isconnected in the operating position with first connector 111. In thiscase the received optical signal directed along the optical receivingpath defined by fiber 204 in FIG. 2 is converted to an ID input signal.This conversion indicated at process block 406 in FIG. 4 comprises aconversion of the optical signal to an electrical signal by transceiver117 in the example of FIG. 2. The ID input signal may then be analyzedas shown at process block 408 in accordance with a suitable process toextract the information encoded into the signal. This analysis isperformed in the example system of FIG. 2 by processor 242 incooperation with data storage 243. In one embodiment, the analysis mayinclude using the ID input signal to query a database stored in datastorage 243 for a corresponding ID signature as indicated at processblock 410. In the event the ID input signal matches an ID signature indata storage, the process may include retrieving connectable deviceinformation that is related to the ID signature in data storage as shownat process block 411. This connectable device information may includeone or more characteristics of the connected device such as a devicetype, or device operating parameters, or a specific serial number forthe connected device. Based on this retrieved information the processmay include generating an identification output as shown at processblock 412.

The process at FIG. 4 includes taking an appropriate action in responseto the identification output resulting from the analysis indicated atprocess block 408. In particular, if the connected device informationdirectly or indirectly indicates that the device is unacceptable to beconnected to the particular control unit, CCU 104 in this example, theprocess may branch from decision box 416 to generating an error messageas shown at process block 418. For example, the process at block 418 mayinclude communicating a message to be displayed by the system to asystem user to indicate that action is necessary. The identificationoutput generated at process block 412 may also include a suitablecommunication to CCU 104 to prevent the CCU from placing the connecteddevice in an operational state. Thus the process may then return fromblock 418 to process block 401 without powering up or otherwise enablingthe connected device for use in the given system. However, if theconnected device information retrieved at process block 411 indicatesthat the device is acceptable for use with the given system,identification output generated at 412 may include a communication toCCU 104 indicating that the connected device is appropriate and may beplaced in an operational state. In this case the illustrated methodproceeds to determine if the identification output generated at 412indicates that the connected device is the same device identified in thelast instance of the process. If the connected device is the samedevice, the process simply continues operation as indicated at processblock 419 and then returns to the start of the process at block 401.However, if the identification output from block 412 indicates that theconnected device is a different device than the device connected duringthe previous instance of the process shown in FIG. 4 or is otherwise anewly connected device, then the process may include enabling the systemto power up the connected device as shown at process block 420. Thispower up according to the device requirement may include providing thecorrect power supply required by the connected device since the systemmay support devices having different input power requirements. After theconnected device is appropriately powered, the process may includeadjusting the communication protocol as necessary to allow communicationwith the connected device as indicated at process block 421, and thencommunicating with the connected device as shown at process block 422.The first device referenced in process block 421 may for examplecomprise a device such as CCU 104 described above, while the seconddevice referenced in process block 422 may comprise the connected devicesuch as camera head 105 described above in connection with FIG. 1. Inone embodiment, the process may include periodically proceeding throughprocess steps 401 to 412 to check for a connected device or newlyconnected device. A loss of return signal in the process shown in FIG. 4would indicate that the device associated with connector 112 has beendisconnected and, in some embodiments, result in an appropriate messageat process block 418. The process may then loop back to process block401 to reinitiate the identification process to identify the nextconnected device.

FIG. 5 shows the process steps performed at second connector 112 toprovide the desired device identification. As shown at process block501, the process at second connector 112 includes receiving the baseoptical signal and directing the signal along the optical signal returnpath arrangement in that connector. The method also includes applyingthe predefined modification pattern to the base optical signal toproduce the optical ID signal as shown at process block 502. In theexample of FIG. 2, this application of the predefined modificationpattern is performed by the pattern of signal attenuators 214 connectedin the fibers 207 a-d, and representing the signal modificationarrangement. Regardless of the specific manner of signal modificationapplied by the signal modification arrangement of the second connector,the optical ID signal is then applied to the output signal path as shownat process block 504 so that the signal may be transferred back to thefirst connector 111 for processing in accordance with the process shownin FIG. 4.

The present invention encompasses numerous variations on the processsteps illustrated in FIGS. 4 and 5. For example, although the processshown in FIG. 4 employs the presence of the optical ID signal returnedto the control unit-side connector as an indication that the device-sideconnector is connected in the operating position, other implementationsof the invention may additionally or alternatively use other detectiontechniques. One such technique may employ a suitable sensor deviceincorporated into the two connectors in addition to or in lieu of theillustrated detection technique. There is also wide variation possiblein the steps used to analyze the ID input signal and ultimately producethe identification output as well as wide variation in theidentification output itself. For example, the connected device data maybe stored in a number of different arrangements to facilitate theretrieval of that data. Where a high level of detail regarding aconnected device is desired, the connected device data may includesimply a serial number correlated to an ID signature, and this serialnumber may first be retrieved and then used to obtain further details onthe connected device from databases that may be external to the controlunit with which the present identification apparatus is employed. Inthis case, the identification output may be the retrieved serial numberwhich is then used to take further action in response to the connectionmade between the two connectors incorporating the identificationapparatus. More generally the identification output may be any output orseries of outputs generated in response to the optical ID signalreturned from the second connector.

It should also be noted that although the invention is describedparticularly in FIGS. 1 and 2 in the context of a device to beidentified being connected to a control unit for that device, theinvention is not limited to this context. In other implementations, thefirst connector such as connector 111 in FIGS. 1 and 2 may be aconnector associated with some device and the second connector may be aconnector associated with some other device or a control unit. In thiscase, the identification process would be to identify that other deviceor control unit. Thus the identification would be in essentially theopposite direction from that shown in the example of FIGS. 1 and 2, andthe action taken in response to an affirmative outcome at decision box416 and a negative outcome at decision box 417 in FIG. 4 might be toenable communication or control from the identified connected device. Ofcourse, in this application the device associated with the firstconnector would include or be associated with a transceivercorresponding to transceiver 117 in FIG. 2 and a processing unitcorresponding to 237 in that figure.

FIGS. 6 and 7 show an example interface corresponding to interface 101in FIG. 1. In this example, FIG. 6 shows a device-side connector 612corresponding to second connector 112 in FIGS. 1 and 2, while FIG. 7shows and example control unit-side connector 711 corresponding to firstconnector 111 in FIGS. 1 and 2. Connector 612 includes at one end aninterface 614 for a device operatively connected to the connector viacable 615. Interface 614 may comprise an optical signal transferarrangement similar to that shown in incorporated application U.S.patent application Ser. No. 15/161,007. Connector 612 may also includean inductive power coupling coil 617 similar to that shown in thisincorporated patent application. However, in addition to interface 614and power coupling coil 617, connector 612 in FIG. 6 includes an opticalpath arrangement corresponding to the optical signal return patharrangement 206 shown in FIG. 2. In the perspective of FIG. 6, the onlyvisible portions of the optical signal return path are openings 618corresponding to lens receiving openings 228 shown in FIG. 2. Theseopenings are visible through protective cover material 621 correspondingto cover material 230 in FIG. 2.

Connector 711 shown in FIG. 7 includes a housing 714 which defines asocket 715 in which connector 612 may be inserted to place the twoconnectors in the operating position. Housing 714 is shown in phantomlines in order to leave certain components of connector 711 visible inthe illustrated perspective. In particular, the perspective of FIG. 7shows openings 718 which correspond to the lens receiving openings 227associated with the optical signal paths shown for first connector 111in FIG. 2. The perspective of FIG. 7 also shows an interface 720 adaptedto cooperate with interface 614 of connector 612 to providecommunications to the device which is associated with connector 612. Inthis case that device comprises camera head 805 shown in FIG. 8connected to connector 612 through cable 615.

When connector 711 and its associated housing 714 are operativelyconnected to a CCU such as CCU 104 in FIG. 1, connector 612 of camerahead 805 may be inserted to an operating position in which deviceinterfaces 614 and 720 are operatively aligned as are the openings 618and 718. According to the process described above in connection withFIG. 4, when connector 612 is so inserted, a base optical signal may beapplied from connector 711 to connector 612. This base optical signal ismodified to produce an optical ID signal which is then directed to firstconnector 711. Processing elements of the identification apparatusassociated with connector 711 then analyze the optical ID signal toproduce an identification output dependent on the result of the analysisand the response options available in the identification system.

As used herein, whether in the above description or the followingclaims, the terms “comprising,” “including,” “carrying,” “having,”“containing,” “involving,” and the like are to be understood to beopen-ended, that is, to mean including but not limited to. Also, itshould be understood that the terms “about,” “substantially,” and liketerms used herein when referring to a dimension or characteristic of acomponent indicate that the described dimension/characteristic is not astrict boundary or parameter and does not exclude variations therefromthat are functionally similar. At a minimum, such references thatinclude a numerical parameter would include variations that, usingmathematical and industrial principles accepted in the art (e.g.,rounding, measurement or other systematic errors, manufacturingtolerances, etc.), would not vary the least significant digit.

Any use of ordinal terms such as “first,” “second,” “third,” etc., inthe following claims to modify a claim element does not by itselfconnote any priority, precedence, or order of one claim element overanother, or the temporal order in which acts of a method are performed.Rather, unless specifically stated otherwise, such ordinal terms areused merely as labels to distinguish one claim element having a certainname from another element having a same name (but for use of the ordinalterm).

In the above descriptions and the following claims, terms such as top,bottom, upper, lower, and the like with reference to a given feature areintended only to identify a given feature and distinguish that featurefrom other features. Unless specifically stated otherwise, such termsare not intended to convey any spatial or temporal relationship for thefeature relative to any other feature.

The term “each” may be used in the following claims for convenience indescribing characteristics or features of multiple elements, and anysuch use of the term “each” is in the inclusive sense unlessspecifically stated otherwise. For example, if a claim defines two ormore elements as “each” having a characteristic or feature, the use ofthe term “each” is not intended to exclude from the claim scope asituation having a third one of the elements which does not have thedefined characteristic or feature.

The above described preferred embodiments are intended to illustrate theprinciples of the invention, but not to limit the scope of theinvention. Various other embodiments and modifications to thesepreferred embodiments may be made by those skilled in the art withoutdeparting from the scope of the present invention. For example, in someinstances, one or more features disclosed in connection with oneembodiment can be used alone or in combination with one or more featuresof one or more other embodiments. More generally, the various featuresdescribed herein may be used in any working combination.

1. An identification apparatus comprising: (a) a first connector havingmounted thereon an optical signal transmission path arrangement and anoptical signal receiving path; (b) a second connector having mountedthereon an optical signal return path arrangement extending from aninput end to an output path, the second connector configured to connectto the first connector in an operating position in which the input endof the optical signal return path arrangement is operatively alignedwith the optical signal transmission path arrangement and the outputpath is operatively aligned with the optical signal receiving path; (c)an optical signal modification arrangement operable to provide apredefined modification to a base optical signal applied at the inputend of the optical signal return path arrangement, the predefinedmodification resulting in an optical ID signal applied at the outputpath of the optical signal return path arrangement; (d) an opticaltransmitter arrangement operable to apply the base optical signal to theoptical signal transmission path arrangement; (e) an optical receiveroperable to receive the optical ID signal from the optical signalreceiving path and produce an ID input signal responsive to the receivedoptical ID signal; and (f) an identification processing unit connectedto receive the ID input signal, the identification processing unit beingoperable to produce an identification output responsive to the ID inputsignal.
 2. The identification apparatus of claim 1 wherein: (a) theoptical signal transmission path arrangement comprises two or moretransmission optical waveguides; (b) the optical signal receiving pathcomprises a receiving optical waveguide; (c) the input end of theoptical signal return path arrangement comprises a respective returnoptical waveguide for each transmission optical waveguide, eachrespective return optical waveguide being located in the secondconnector so as to operatively align with the respective transmissionoptical waveguide when the second connector is connected with the firstconnector in the operating position; (d) the output path comprises anoutput optical waveguide located in the second connector so as tooperatively align with the receiving optical waveguide when the secondconnector is connected with the first connector in the operatingposition; and (e) an optical coupler positioned in the optical signalreturn path arrangement so as to optically couple each return opticalwaveguide to the output optical waveguide.
 3. The identificationapparatus of claim 2 wherein the optical signal modification arrangementcomprises at least one optical signal attenuator, each respectiveoptical signal attenuator operatively connected in a respective one ofthe return optical waveguides.
 4. The identification apparatus of claim2 wherein each of the two or more transmission optical waveguidesincludes a respective transmission end portion extending substantiallyparallel to a receiving end portion of the receiving optical waveguide.5. The identification apparatus of claim 1 wherein: (a) the opticalsignal transmission path arrangement and the optical signal receivingpath are mounted within a transmit and receive alignment block which ismounted in the first connector; and (b) the optical signal return patharrangement is mounted in a return alignment block which is mounted inthe second connector.
 6. The identification apparatus of claim 1wherein: (b) the first connector includes a medical instrument controlunit interface; and (b) the second connector includes a medicalinstrument interface configured to operatively connect to the medicalinstrument control unit interface when the second connector is connectedto the first connector in the operating position.
 7. The identificationapparatus of claim 1 wherein the identification processing unitcomprises: (a) data storage storing a number of ID signatures, eachrespective ID signature related in the data storage to respectiveconnectable device information; and (b) a processor operable to, inresponse to the received ID input signal, (i) locate in the data storageone of the ID signatures corresponding to the ID input signal andretrieve the respective connectable device information related to thelocated ID signature, and (ii) generate the identification output basedon the respective device information related to the located IDsignature.
 8. A method comprising: (a) transmitting a base opticalsignal from a first connector to a second connector, the base opticalsignal including two or more base optical signal components; (b)directing the base optical signal along an optical signal return patharrangement associated with the second connector; (c) applying apredefined modification pattern to the two or more base optical signalcomponents as the base optical signal is directed through the opticalsignal return path arrangement, the predefined modification patternresulting in an optical ID signal applied at an output waveguide of theoptical signal return path arrangement; (d) directing the optical IDsignal from the output waveguide to a receiving optical waveguide of thefirst connector; and (e) receiving the optical ID signal at the firstconnector and producing an identification output in response to thereceived optical ID signal.
 9. The method of claim 8 wherein thepredefined modification pattern comprises a pattern of signalattenuation among the two or more base optical signal components. 10.The method of claim 8 wherein: (a) transmitting the base optical signalincludes directing each respective base optical signal component over adifferent respective transmission optical waveguide associated with thefirst connector; and (b) directing the base optical signal along theoptical return path arrangement includes directing each base opticalsignal component along a different respective return optical waveguideassociated with the second connector.
 11. The method of claim 10 whereinthe predefined modification pattern comprises a pattern of signalattenuation among the two or more base optical signal components. 12.The method of claim 8 wherein the two or more base optical signalcomponents are temporally offset.
 13. The method of claim 8 wherein eachof the two or more base optical signal components is transmitted at adifferent respective modulation frequency.
 14. The method of claim 8further including: (a) producing an ID input signal in response to theoptical ID signal; (b) locating in data storage an ID signaturecorresponding to the ID input signal; (c) retrieving connectable deviceinformation related in the data storage to the located ID signature; and(d) generating an identification output based on the retrieved deviceinformation.
 15. An apparatus comprising: (a) an instrument; (b) aninstrument connector operatively connected to the instrument, theinstrument connector configured to connect in an operating position witha control unit connector associated with a control unit for theinstrument; (c) an optical signal return path arrangement mounted in theinstrument connector, the optical signal return path arrangementextending from an input end to an output optical waveguide; and (d) anoptical signal modification arrangement associated with the opticalsignal return path arrangement and operable to provide a predefinedmodification to a base optical signal applied at the input end of theoptical signal return path arrangement, the predefined modificationresulting in an optical ID signal applied at the output opticalwaveguide.
 16. The apparatus of claim 15 wherein the input end of theoptical signal return path arrangement includes two or more returnoptical waveguides and an optical coupler coupling each return opticalwaveguide to the output optical waveguide.
 17. The apparatus of claim 16wherein the optical signal modification arrangement comprises at leastone optical signal attenuator, each respective optical attenuatoroperatively connected in a respective one of the return opticalwaveguides.
 18. The apparatus of claim 16 wherein each of the two ormore return optical waveguides includes a respective end portionextending substantially parallel to an output end portion of the outputoptical waveguide.
 19. The apparatus of claim 15 wherein the opticalsignal return path arrangement is mounted in a return alignment block inthe instrument connector.
 20. The apparatus of claim 15 wherein theinstrument connector includes an instrument interface configured tooperatively connect to a control unit interface of the control unitconnector when the instrument connector is connected to the control unitconnector in the operating position.